/*
*
* jQuery listnav plugin
* Copyright (c) 2009 iHwy, Inc.
* Author: Jack Killpatrick
*
* Version 2.1 (08/09/2009)
* Requires jQuery 1.3.2, jquery 1.2.6 or jquery 1.2.x plus the jquery dimensions plugin
*
* Visit http://www.ihwy.com/labs/jquery-listnav-plugin.aspx for more information.
*
* Dual licensed under the MIT and GPL licenses:
*   http://www.opensource.org/licenses/mit-license.php
*   http://www.gnu.org/licenses/gpl.html
*
*/

(function($) {
  $.fn.listnav = function(options) {
    var opts = $.extend({}, $.fn.listnav.defaults, options);
    var letters = ['_', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '-'];
    var firstClick = false;
    opts.prefixes = $.map(opts.prefixes, function(n) { return n.toLowerCase(); });

    return this.each(function() {
      var $wrapper, list, $list, $letters, $letterCount, id;
      id = this.id;
      $wrapper = $('#' + id + '-nav'); // user must abide by the convention: <ul id="myList"> for list and <div id="myList-nav"> for nav wrapper
      $list = $(this);

      var counts = {}, allCount = 0, isAll = true, numCount = 0, prevLetter = '';

      function init() {
        $wrapper.append(createLettersHtml());

        $letters = $('.ln-letters', $wrapper).slice(0, 1); // will always be a single item
        if (opts.showCounts) $letterCount = $('.ln-letter-count', $wrapper).slice(0, 1); // will always be a single item

        addClasses();
        addNoMatchLI();
        if (opts.flagDisabled) addDisabledClass();
        bindHandlers();

        if (!opts.includeAll) $list.show(); // show the list in case the recommendation for includeAll=false was taken

        // remove nav items we don't need
        //
        if (!opts.includeAll) $('.all', $letters).remove();
        if (!opts.includeNums) $('._', $letters).remove();
        if (!opts.includeOther) $('.-', $letters).remove();

        $(':last', $letters).addClass('ln-last'); // allows for styling a case where last item needs right border set (because items before that only have top, left and bottom so that border between items isn't doubled)
        
        if ($.cookie && (opts.cookieName != null)) {
          var cookieLetter = $.cookie(opts.cookieName);
          if (cookieLetter != null) opts.initLetter = cookieLetter;
        }

        // decide what to show first
        //
        if (opts.initLetter != '') {
          firstClick = true;
          $('.' + opts.initLetter.toLowerCase(), $letters).slice(0, 1).click(); // click the initLetter if there was one
        }
        else {
          if (opts.includeAll) $('.all', $letters).addClass('ln-selected'); // showing all: we don't need to click this: the whole list is already loaded
          else { // ALL link is hidden, click the first letter that will display LI's
            for (var i = ((opts.includeNums) ? 0 : 1); i < letters.length; i++) {
              if (counts[letters[i]] > 0) {
                firstClick = true;
                $('.' + letters[i], $letters).slice(0, 1).click();
                break;
              }
            }
          }
        }
      }

      // positions the letter count div above the letter links (so we only have to do it once: after this we just change it's left position via mouseover)
      //
      function setLetterCountTop() {
        $letterCount.css({ top: $('.a', $letters).slice(0, 1).offset({ margin: false, border: true }).top - $letterCount.outerHeight({ margin: true }) }); // note: don't set top based on '.all': it might not be visible
      }

      // adds a class to each LI that has text content inside of it (ie, inside an <a>, a <div>, nested DOM nodes, etc)
      //
      function addClasses() {
        var str, firstChar, firstWord, spl, $this, hasPrefixes = (opts.prefixes.length > 0);
        $($list).children().each(function() {
          $this = $(this), firstChar = '', str = $.trim($this.text()).toLowerCase();
          if (str != '') {
            if (hasPrefixes) {
              spl = str.split(' ');
              if ((spl.length > 1) && ($.inArray(spl[0], opts.prefixes) > -1)) {
                firstChar = spl[1].charAt(0);
                addLetterClass(firstChar, $this, true);
              }
            }
            firstChar = str.charAt(0);
            addLetterClass(firstChar, $this);
          }
        });
      }

      function addLetterClass(firstChar, $el, isPrefix) {
        if (/\W/.test(firstChar)) firstChar = '-'; // not A-Z, a-z or 0-9, so considered "other"
        if (!isNaN(firstChar)) firstChar = '_'; // use '_' if the first char is a number
        $el.addClass('ln-' + firstChar);

        if (counts[firstChar] == undefined) counts[firstChar] = 0;
        counts[firstChar]++;
        if (!isPrefix) allCount++;
      }

      function addDisabledClass() {
        for (var i = 0; i < letters.length; i++) {
          if (counts[letters[i]] == undefined) $('.' + letters[i], $letters).addClass('ln-disabled');
        }
      }

      function addNoMatchLI() {
        $list.append('<li class="ln-no-match" style="display:none">' + opts.noMatchText + '</li>');
      }

      function getLetterCount(el) {
        if ($(el).hasClass('all')) return allCount;
        else {
          var count = counts[$(el).attr('class').split(' ')[0]];
          return (count != undefined) ? count : 0; // some letters may not have a count in the hash
        }
      }

      function bindHandlers() {

        // sets the top position of the count div in case something above it on the page has resized
        //
        if (opts.showCounts) {
          $wrapper.mouseover(function() {
            setLetterCountTop();
          });
        }

        // mouseover for each letter: shows the count above the letter
        //
        if (opts.showCounts) {
          $('a', $letters).mouseover(function() {
            var left = $(this).position().left;
            var width = ($(this).outerWidth({ margin: true }) - 1) + 'px'; // the -1 is to tweak the width a bit due to a seeming inaccuracy in jquery ui/dimensions outerWidth (same result in FF2 and IE6/7)
            var count = getLetterCount(this);
            $letterCount.css({ left: left, width: width }).text(count).show(); // set left position and width of letter count, set count text and show it
          });

          // mouseout for each letter: hide the count
          //
          $('a', $letters).mouseout(function() {
            $letterCount.hide();
          });
        }

        // click handler for letters: shows/hides relevant LI's
        //
        $('a', $letters).click(function() {
          $('a.ln-selected', $letters).removeClass('ln-selected');

          var letter = $(this).attr('class').split(' ')[0];

          if (letter == 'all') {
            $list.children().show();
            $list.children('.ln-no-match').hide();
            isAll = true;
          } else {
            if (isAll) {
              $list.children().hide();
              isAll = false;
            } else if (prevLetter != '') $list.children('.ln-' + prevLetter).hide();

            var count = getLetterCount(this);
            if (count > 0) {
              $list.children('.ln-no-match').hide(); // in case it's showing
              $list.children('.ln-' + letter).show();
            }
            else $list.children('.ln-no-match').show();

            prevLetter = letter;
          }

          if ($.cookie && (opts.cookieName != null)) $.cookie(opts.cookieName, letter);


          $(this).addClass('ln-selected');
          $(this).blur();
          if (!firstClick && (opts.onClick != null)) opts.onClick(letter);
          else firstClick = false;
          return false;
        });
      }

      // creates the HTML for the letter links
      //  
      function createLettersHtml() {
        var html = [];
        for (var i = 1; i < letters.length; i++) {
          if (html.length == 0) html.push('<a class="all" href="#">ALL</a><a class="_" href="#">0-9</a>');
          html.push('<a class="' + letters[i] + '" href="#">' + ((letters[i] == '-') ? '...' : letters[i].toUpperCase()) + '</a>');
        }
        return '<div class="ln-letters">' + html.join('') + '</div>' + ((opts.showCounts) ? '<div class="ln-letter-count" style="display:none; position:absolute; top:0; left:0; width:20px;">0</div>' : ''); // the styling for ln-letter-count is to give us a starting point for the element, which will be repositioned when made visible (ie, should not need to be styled by the user)
      }

      init();
    });
  };

  $.fn.listnav.defaults = {
    initLetter: '',
    includeAll: true,
    incudeOther: false,
    includeNums: true,
    flagDisabled: true,
    noMatchText: 'No matching entries',
    showCounts: true,
    cookieName: null,
    onClick: null,
    prefixes: []
  };
})(jQuery);